Degasser



s- 19, 1958 w. E. LEIBING 2,848,202

DEGASSER Filed Jan. 6, 1956 2 Sheets-Sheet 1 TI'TE .1

IN VEN TOR.

W a-M ATTORNEY Aug. 19, 1958 w. E. LEIBING EGASSER 2 Sheets-S 2 Filed Jan. 6. 1956 Q. A Q.

III I R I a INVENTOR.

xlrram fr United States Patent DEGASSER William E. Leibillgsv Pasadena, Calif. Application January 6, 1956, Serial'No. 557,789

6 Claims. (Cl. 261-41) The present invention relates to an induction system of an internal combustion engine and more particularly to a degasser for use in conjunction with said'system.

The invention is primarily concerned with a device or system for preventing, fumes from being discharged through the exhaust pipe of an automobile when said vehicle is coasting down grade or decelerating, from a rather high rate of speed. During this deceleration or coasting the vehicle is usually driving the engine and the throttle valve of the carburetor is closed, thus causing the vacuum in the intake manifold to rise substantially above that existing during normal engine idling and the compression ratio in the cylinders to fall from, for examble, 8 to 1 to as low as 1.2 to 1. Charges formed under these conditions are small and often lean and fail to ignite at the low compression. The unignited charges are discharged from the cylinders through the exhaust pipe into the atmosphere as raw or partially burned fuel vapors, contributing seriously in some cities to the prevailing smog conditions. Further, in some instances the fumes are ignited in the exhaust pipe by the residual heat or the firing of subsequent charges in the cylinders, producing popping in the exhaust pipe and muffler.

Since engine operation is not necessary when the vehi cle is driving the engine, the discharge of fumes has been prevented to a limited extent in the past by employing a device on or in conjunction with the carburetor for completely interrupting the operation of the idle system by shutting off the flow of fuel therethrough during the time the load is driving the engine. While thistype of device has effectively eliminated the formation-of lean charges from the idle fuel, unfireable charges are also sometimes formed by fuel spilling into the induction passage from the main jet of the carburetor by the bouncing, tossing and jarring of the vehicle as it is decelerating or coasting. This is primarily caused by ocsillation of the floats in the fuel bowl opening the fuel inlet valve and admitting excess fuel and raising the level in the bowl to a point where the fuel flows through the main jet and spills intermittently into the induction passage. This spilling provides either excessively rich or excessively lean charges which do not fire in the cylinders and are discharged as fumes through the exhaust pipe into the atmosphere. It is therefore one of the principal objects of the present invention to provide a device or system which interrupts the flow of fuel from both the idle system and the main jet of the carburetor when load is driving the engine such as to create an intake manifold vacuum in excess of that normally existing during engine idling.

Another object of. the present invention is to provide a device or system for shutting off the-flow of fuel through the idle system of the carburetor and to the fuel bowl whenever the intake manifold vacuum reaches a predetermined degree above that existingat normal idling. Another object of the'invention is to provide a device or system of the, aforesaid type which can be readily installed on conventional internal combustion engineswithice 2 out special bosses or fixtures provided on. the various units to which itis attached. I

Still another object; is to provide a relatively simple but effective degasser for internal combustion engines which is adapted to give long trouble-free operation and which can be readily serviced and repaired if operation failure occurs.

A further object of the invention is to provide a device for interrupting theflow offuel to the, fuelbowl of a float type carburetorwhenever the manifold vacuum reaches a predetermined degree.

Another object of the invention isto provide a means for preventing the discharge of fuel from the main discharge system of a carburetor when the vehicle is driving theengine.

Additional objects and advantages of the present invention will become apparent'from the following description and accompanying drawings, wherein:

Figure lis an elevational' view of anintake manifold, carburetor and my degasser system, showing the various units comprising the, system mounted inoperative position with relation to the manifold and carburetor; and

Figure 2 is a schematic view of the induction passages of a double barrel carburetor and cross sectional views of the several units of my system showing the units operatively connected to each other and to the carburetor and the fuel line thereto.

My degasser system consists principally of a unit for shutting off the flow of fuel from the idle system of the carburetor, a unitin the main fuelline to the carburetor for shutting off the fuel flow to the fuel bowl, and a unit for controlling the vacuum operating the first two units of the system. Referring more specifically to the drawing, numeral 10 designates a. conventional manifold for an internal combustion engine, .12 a carburetor mounted on said manifold, 14 a fuel line connecting the carburetor with a source of fuel, 16 a vacuum operated unit mounted on the carburetor for shutting, off thefi'ow of fuel from the idle system, 18 a vacuum operated'valve unit in the fuel line, and 20 a unitmounted on'the manifold for controlling the operation of units 16 and 18. Valve unit 18 is mounted in the fuelline between the carburetor and the. fuel pump.

Unit 16 consists of two sections 22 and 24 having'opposed annular flanges 26 and 28, respectively, joined togetherby screws, or by deforming-the metal of one flange over the other, or by' any other suitable means. A flexible diaphragm 32 is clamped between sections 22 and 24 separating the unit-into two chambers 34 and 36, the former chamber being vented to atmospheric pressure by holes 37 and the latter being connected to'a sourceof vacuum through conduit 38. Section"'24' is provided with a stem 39 having a threaded portion for screwing into the-threaded bore 40 of the idle adjustment screw of the standard carburetor and containing a central passage 41 through which air is adapted to flow from the atmosphere through holes 37' and chamber 34'. Stem 39' terminates in a-conical point 42 which in cooperation with seat 44 serves as an idle adjustment valve, the opening between said conicaltip and said seat. being adjusted' by the rotation of stem 39in or'out of the bore 40. Passage 41 is connected to a chamber. 46' of'the idle system 48 of thecarburetor by lateral passages 50. In making an adjustment of point 42 relative to seat 44 the entire unit 16 is rotated and) the desired setting of said point is maintained by a spring 52 around stem 39 bearing-against. the idle screw boss and section 24. A valve 54 is provided at the entrance of passage 41 and consists of an annularvalve seat 56' and a disc shaped gasket 57 carried in a cup 58 secured to one side of diaphragm 32 bya rivet 60 extending through the" diaphragm and a spring retainer 62. The gasket is maintained on its seat throughout normal operation of the engine by a spring 64 reacting between spring retainer 62 and the inside end wall of section 22. This spring is calibrated to yield to the vacuum transmitted to chamber 36 when vacuum control unit responds to the rise of manifold vacuum to a point substantially above that existing at normal idling.

Vacuum operated valve unit 18 consists of a housing and a valve chamber 82 connected by a passage 84 with the fuel supply line from the fuel pump and connected by passages 86, chamber 88 and passage 90 with the fuel line leading to the carburetor. A movable valve member 92 in cooperation with annular valve seat 94 controls the flow of fuel to the carburetor and is urged to its closed position by a spring 96 reacting between said valve member and one end of chamber 82. A diaphragm 98 divides the housing into two chambers 100 and 102 and a diaphragm 104 seals chamber 102 from fuel chamber 88, chamber 100 being connected by a passage 106 with a source of vacuum and chamber 102 being vented to the atmosphere through hole 108. Valve member 92 is operatively connected with diaphragm 98 by a linkage consisting of a stem 110, discs 112 and 114 on diaphragm 104 and rivet 116 extending through diaphragm 98 and securing cup shaped members 118 and 119 to opposite sides of said diaphragm. A spring 120 which is substantially stronger than spring 96 reacting between cup shaped member 119 and the inside end wall of chamber 100 holds valve member 92 off its seat during all normal operating conditions of the engine, thus permitting the fuel to flow freely to the carburetor fuel bowl. When the vacuum is transmitted to chamber 100 as unit 20 responds to a rise in manifold vacuum to a point substantially above that prevailing during normal idling, spring 120 is compressed sufiiciently to permit spring 96 to close valve member 92.

The vacuum control unit 20 is mounted on the intake manifold by stern threadedly received in opening 132 in a boss 134 on the manifold and contains a valve chamber 136 connected to the intake manifold by passage 138 and connected to vacuum lines 139 and 140 by passage 142. The vacuum transmitted from the manifold through chamber 136 is controlled by a valve 144 which is adapted to seatvat the opening into passage 138 and which is urged to its unseated position by a spring 148 reacting between an enlarged portion of said valve and the upper end of chamber 136. The unit contains a chamber 150 connected to the intake manifold through passages 152 and 138 and closed at one end by a flexible diaphragm 154 clamped between two sections of the unit housing, which together with another diaphragm 156 forms a second chamber 158. Valve 144 is operatively connected to diaphragm 154 by a linkage consisting of a pair of buttons 160 and 162 on opposite sides of diaphragm 156 and a lug 164 on one side of diaphragm 154 and is urged to its closed position by a spring in chamber 150 reacting between diaphragm 154 and a spring adjustment means 172 consisting of a spring retainer 174 and a screw 176 threadedly received in the end wall of chamber 150. A lock nut 178 is provided to retain hte adjustment screw in any desired position. Spring 170 is substantially stronger than. spring 148 and holds valve 144 in closed position until a predetermined vacuum has been reached in the intake manifold and transmitted to chamber 150 through passages 138 and 152.

Chamber 158 is connected by passage 180 and conduit 182 with a port 184 in the induction passage of the carburetor adjacent the leading edge of one of the throttle valves 186 or 186' on the air intake side thereof. As the throttle valve is opened and the leading edge passes port 184 manifold vacuum is immediately transmitted to chamber 158, thus equalizing the pressures on opposite sides of diaphragm 154 so that spring 170 can quickly return valve 144 to its closed position and hold it in that position so long as the throttle valve is in open position. The spark advance port of a vacuum spark unit may be used as the vacuum connection for chamber 158 and conduit 182 can be connected into the vacuum line for the spark advance mechanism. The connection to the port adjacent the throttle valve can be dispensed with without seriously interfering with the satisfactory operation of my degasser system; however, this connection accelerates the response of the system in readjusting to normal engine operation.

The action of the control unit 20 is positive, on either off or on positions .as valve 144 seats and un-seats. The enlarged portion of the valve has a predetermined clearance in chamber 136 and the cavity 188 at the end of the valve is vented to atmosphere by a port 190, so that when the valve is on its seat atmospheric pressures are a quickly restored in units 16 and 18. As a result of this venting, when a vacuum of above idling is introduced into the chamber 150, a vacuum substantially less than manifold vacuum, for example from 10 to 15 inches of mercury, is transmitted to units 16 and 18. By quickly restoring atmospheric pressure in units 16 and 18 when valve 144 closes the engine quickly resumes normal oper- 511011,

In the operation of the degasser system disclosed herein, when the engine is driving the vehicle or merely idling, the vacuum prevailing in the intake manifold and in chamber 150 is not sufficient to move diaphragm 154 downwardly against spring 170, thus valve 144 remains closed and no vacuum is transmitted to either the idle cut-off unit 16 or the fuel valve unit 18. Consequently valve 54 is maintained in closed position by spring 64 and valve 92 is maintained in open position by spring 120, and the carburetor operates in the same manner as if the degasser system were not installed on the engine. If however the vehicle is decelerated rapidly from at least a moderate rate of speed or if the vehicle is coasting down a long grade, the vehicle drives the engine, creating in the intake manifold a high vacuum in the range of 24 to 26 inches of mercury. This high vacuum is transmitted through passage 138 and passage 152 to chamber 150 and acts on diaphragm 154 with sufficient force to overcome spring 170 which has been set to yield to the vacuum in said range. When diaphragm 154 moves downwardly, spring 148 forces the valve away from its seat following the full downward movement of diaphragm 154.

When valve 144 opens manifold vacuum is transmitted through conduit 140 to chamber 36 where it acts on diaphragm 32 and moves valve 54 to its open position in opposition to spring 64. Air is thus permitted to flow through ports 37 into passage 41 and through passages 50 into the idle system, bleeding out the idle system so that no fuel will be discharged therefrom While the intake manifold vacuum is excessively high. Simultaneously with the foregoing operation of valve 54, vacuum is transmitted to chamber 100 where it acts on diaphragm 98 moving it to the right as seen in the drawings, thus permitting spring 96 to close valve 92 and thereby interrupt the flow of fuel to the carburetor fuel bowl. With the idle system rendered inoperative and the supply of fuel interrupted, all fuel charges to the engine are stopped and as a result no obnoxious fumes are dis charged from the vehicle and no popping occurs in the exhaust pipe and muffler. When the vacuum in the intake manifold returns to normal, valve 144 closes cutting off the vacuum to both chambers 36 and 100 permitting valve 54 to close and valve 92 to open. The idle system and the fuel supply line are thus returned to normal operation.

While only one embodiment of my invention is specifically described herein, various changes can be made in the system or parts thereof without departing from the scope of the invention. For example unit 16 can be so designed that instead of bleeding air into the idle systerm it will positively cut off the flow of fuel from the system. Further, instead of cutting ofi the fuel supply in the main fuel supply line, a valve can be employed in conjunction with the main discharge jet or nozzle of the carburetor to interrupt the flow of fuel therein when the manifold vacuum becomes excessively high.

I claim:

1. A degasser for an internal combustion engine having an intake manifold, a carburetor including an idle system, an induction passage with a throttle therein, and a fuel supply line, comprising a vacuum actuated valve means for interrupting the flow of fuel from said idle system, a vacuum actuated valve means for interrupting the flow of fuel through said supply line, a vacuum control unit connected to said manifold, a valve in said unit for controlling the vacuum transmitted to said valve means, a means for opening said valve when the manifold vacuum reaches a predetermined degree above that existing at normal idling, and a means connected to the induction passage on the upstream side of the throttle for assisting in the closing of said valve when the throttle is opened.

2. A degasser for an internal combustion engine having an intake manifold, a carburetor including an idle system, an induction passage with a throttle therein and a fuel supply line, comprising a vacuum actuated valve means for interrupting the flow of fuel from said idle system, a vacuum actuated valve means for interrupting the fiow of fuel through said supply line, a valve responsive to manifold vacuum for controlling the vacuum transmitted to said valve means, a means for opening said valve when the manifold vacuum reaches a predetermined degree above that existing at normal idling, and a means connected to the induction passage of the air inlet side of the throttle for assisting in the closing of said valve when the throttle is opened.

3. A degasser for an internal combustion engine having an intake manifold, a carburetor including an idle system, a main discharge jet and an induction passage with a throttle therein, comprising a vacuum actuated valve means for interrupting the flow of fuel from said idle system, a vacuum actuated valve means for interrupting the flow of fuel from said discharge jet, a vacuum control unit connected to said manifold, a valve responsive to manifold vacuum in said unit for controlling the vacuum transmitted to said valve means, a means for opening said valve when the manifold vacuum reaches a predetermined degree above that existing at normal idling, and a means connected to the induction passage on the upstream side of the throttle for assisting in the closing of said valve when the throttle is opened.

4. A degasser for an internal combustion engine having 6 an intake manifold, a carburetor including an idle system, a main discharge jet and an induction passage with a throttle therein, comprising a vacuum actuated valve means for interrupting the flow of fuel from said idle system, a vacuum actuated valve means for interrupting the flow of fuel from said jet, a valve responsive to manifold vacuum for controlling the vacuum transmitted to said valve means, a means for opening said valve when the mamfoldyacuum reaches a predetermined degree above thatexistmg at normal idling, and a means connected to the induction passage on the air inlet side of the throttle for assisting in the closing of said valve when the throttle is opened.

5. A degasser for an internal combustion engine having an intalre manifold, a carburetor including a main discharge et and an induction passage with a throttle there- 1n, comprising a vacuum actuated valve means for interruptmgthe flow of fuel from said discharge jet, a' valve responsive to manifold vacuum for controlling the vacuum transmitted to said valve means, a means for opening said valve when the manifold vacuum reaches a predetermined degree above that existing at normal idling, and a means connected to the induction passage on the air inlet side of the throttle for assisting in the closing of said valve when the throttle is opened.

6 A degasser for an internal combustion engine having an lntake manifold anda carburetor including an idle system, and an induction passage with a throttle therein, comprising a vacuum actuated valve means for interrupting the flow of fuel from said idle system, a vacuum control unit connected to said manifold, a valve for controlling the vacuum transmitted to said valve means, a means for opening said valve when the manifold vacuum reaches a predetermined degree above that existing at normal idling, and a means connected to the induction passage on the air inlet side of the throttle for assisting in the closing of said valve when the throttle is opened.

References Cited in the file of this patent UNITED STATES PATENTS 1,956,992 Mallory May 1, 1934 2,057,215 Smith Oct. 13, 1936 2,094,555 Von Hilvety Sept. 28, 1937 2,212,936 Hoof Aug. 27, 1940 2,692,766 Carlson et al. Oct. 26, 1954 2,742,270 McClain Apr. 17, 1956 2,763,285 Reeves Sept. 18, 1956 FOREIGN PATENTS 466,164 Great Britain May 18, 1937 800,897 France May 11,' 1936 

